Apparatus for testing fluorescent lamps, control units, and circuits



May 27, 1941. G. w. JAMES 2.2435755 APPARATUS FOR .TESTING FLUORESCENT IJMS, CONTROL UNITS, AND CIRCUITS Filed July l5, 1940 S'SheetS-Sheet l WD qu..- P305:

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May 27, 1941. G, w, JAMES 2,243,755

APPARATUS FOR TESTING FLUORESCENT LAMPS, CONTROL UNITSr AND OIROU ITS Filed July 13,v 1940 8 Sheets-Sheet /zeJ May 27, 1941. G. w. JAMES APPARATUS FOR TESTING FLUORESCENT LAMPS, CONTROL UNITS, AND CIRCUITS Filed July 13, 1940 8 Sheets-Sheet 4 Miglior/zeg.

lMay 27,1941. G `W JAMES 2,243,755

APPARATUS FOR TESTING FLUORESCENTYLAMPS, CONTROL UNITS, AND CIRCUITS 4Filed July 13. 1940. 8 Sheets-Sheet 5 JZUeI/z'of `Gered@ y/z@ Mmes 8 Sheets-Sheet 6 May 27,` 1941. G. w. JAMES APPARATUS FOR TESTING FLORESCENT LAMP-S', CONTROL UNITS, AND CIRCUITS A Filed July 13. 1940 Gef-ald. mes

n. Y v @Q May 27, 1941. Q w JAMES 2,243,755 APPARATUS FCR TESTING FLUoREsCENT LAMPS, CONTROL UNITs, AND CIRCUITS Filed July 15, 1940. 8 Sheets-Sheet 7 May27,1941. awJAMgS 2,243,155

APPARATUS FOR TESTING FLUORESCENT LAMPS, CONTROL UNITS, AND CIRCUITS Filed July 13, 1940 8 Sheets-Sheet 8 Patented May 27, 1941 e I A STATES Parar Nortica APPARATUS FOR. TESTING FLUGRESUENT LAMPS, CONTROL UNTS, AND CCUITS Gerald Wayne James, Chicago, lll., asser to Zephyr-Lite Mfg. Co., Chicago, Ill., a corporation of Illinois application July la, i940, .serial No. 345,365

11 claims. (lol. ris-iss) My invention relates to electrical lighting, and changes and modications may be resorted to particularly to an apparatus for testingtthe varwithout departure from the spirit of the claims ious control units, circuits, and lamps employed forming a part hereof. And Whereas I have so in the present lform of iiuorescent lighting, and described my invention, it is to be understood more specically to a portable type of testing that the words I use are Words of description unit embodying the equipment necessary to test and not of limitation, and that similar characthe lamps, control unit and circuits, either as ters of reference indicate similar parts throughindependent units or in various combinations out the several views of lthe f drawings, and thereof, and either when assembled or installed wherein: in the xtures or when dis-assembled and :prior l Fig. 1 is a plan or the panel board, illustratto installation. ing the various manually controlled switches, Present day iiuorescent lighting circuits involve meter. glow lamp, sockets and Ding-in leads; a. variety of sizes of lamps, each with a diierent Fig. 2 is a' schematic Circuit diagram 0f the voltage and current requirement, a, multitude of entire and Complete test unit which I employ fOI controlling and starting devices, and many difdetermining the operating -characteristics of the ferent circuit combinations, au of which require lamp, xture, and control units as usually used checking and testing, both prior to and after influorescen-t lighting;

installation. Fig. 3 is a schematic circuit diagram-a part It is therefore an object of my invention to 0f Fig- A2shovving that portion enlplOyed in the provide a portable unit suitably adaptable to test testing 0f the lamp Only;

the many varieties oi lamps, the various con- .Fie- 4 is e simplified and condensed diagram of v trols and circuits both prior to and after installa- F1g 3; t tion and fixture assemblies: a unit whlch is port- Fig. 5 is the schematic circuit diagram-a Peri;

able and readily usable in the eld for determinof Fig. 2-S110Wing that portion Only 0f the gening trouble encountered in wired circuits, witheral circuit employed in testing control units,

out the risk of destroying lamps' or other equip- Such as reaeiers Comprising the Various Comblmen-t; a unit which will give an accurate and nations. such es shown at Fiss. 6 to 9 inclusive: positive indication When al1 the circuit compo- Fig- 6 illustrates e Simple fOInl Of Single lamp. nents are correct for the operation of the lamp; 110 VOlt reaeier O1 impedance fOr use With an g unit which will give a,V varying negative indiexternal Starting SW'itCh for a 15 and 20 Watt cation when circuit components are not correct lamp ShOWn Connected in the Circuit 0f Fig- 5 for lamp operation; a unit which will indicate shown in simplified form; when the complete installation is not properly Fig. 7 like Fig. 6 illustrates a two lamp, 15 or made due to incorrect wiring, the use of the 20 watt, 110-125 volt reactor or ballast, with wrong control unit or defective equipment such built in starting compensator for use with exas the reacter, choke coil, condenser or starting --ternal starting switch;4

switch. Fig. 8 further illustrates a simple l5 or 20 watt Further objects of my invention are to provide single lamp reacter with builtin starting switch;

a unit tester which is simple in desisn'and oon- Fig. 9 is a like schematic diagram of a 30 or 4o struction, efcieni. easy to Operate. accurate, edu- 40 watt single lamp reactor, 11o-125 volts, for use cational and a profitable investment for the elecwith an external starting switch shown connecttrlcal contractor, wireman, service-man, engied in the'circuit of M 5 as before;l

neer, or laboratory technician in his every-day routinework of testing uorescent lamps, wired circuits and control apparatus such as reacters Fig. 10 is a schematic diagram of that portion of Fig. 2 employed in the testing of starting switches' or choke coils, auxiliaries, ballasts, valves, or i compensators, and starting switches (neon, thergig* i185 a' snlplmcia'tion of Fig- 10' y mal or magnetic), either cartridge and plug in g' a -sc em -c diagram of that portion .type or the enclosed and bunt n type of Fig. 2 used in the testing of the control units.;

'My present invention has these and other ob- 50 after assembly in 'the lighting fixture, and in- ;lects, all of which are explained in detail and Nudes the connections to the fixture; f may be more readily understood when read in F18. 13 is a simplied diagram 0f F18. 12; and commotion with the accompanying drawings Fig. 14 is a schematic diagram of a like but (eight sheets) which illustrate a preferred emmodiiied` form of unit employed in testing the \bodiment of my invention, it being manifest that tV control units such as 'the reacter and starting When auxiliary power is supplied to the test kit which embodies the circuit shown at Fig. 2,

independently of the source of power supplied to the fixture, I am enabled to:

(a) Test fluorescent lamp of the low voltage or Mazda type.

(b) Test reacter or control equipment variously known as auxiliaries, ballasts, choke coils.

' valves or compensators. Y

(c) Test starting switch, which may be of the thermal type, magnetic type, or cartridge or plugin type sometimes referred to as a neon glow switch, which in reality is usually a thermal type employing a neon or other gas lled tube for the heating element in lieu of the usual coil. The starting switch may be tested either in combination with the reacter, such as where' the starting switch is built in and enclosed and made a part of the control equipment per se, or the starting switch may be tested separately and alone' as in the case of the cartridge or plug-in type.

Whenpower is supplied directly to the ln- -stalled fixture and no auxiliary power is supplied to the test equipment, I may:

(a) Test lamp individually.

(b) Test reacter individually.

(c) Test starting switch individually.

(d) Test for correctness of fixture wiring.

(e) Test lamp and reacter in combination.

`(f) Test reacter and starting switch in combination. g

(g) Test lamp, reacter and starting switch in combination.

And as each of the above listed tests is usually separate and distinct from the others, I have illustrated each such circuit separate and apart from the inter-connected circuit of Fig. 2 and now describe each in turn, reference being had to the foregoing.

The specic circuit for testing thefluorescent lamp A is indicated at Fig. 3. This lamp may I be of any type of gas filled tube having a suitable D3 and D4, and each gang has the positions a, b, c and d adapted to be engaged by a sliding contact arm common to each gang and independent electrically from all others, as indicated I at Fig. 2. The switch E is like in form, being a four (4) gang indicated El, E2, E3 and El, with six (6) positions b, c, d, e and f oneach gang. And switch F is also like both D and E except that it has three (3) gangs with five positions each, a, b, c, d and e respectively.

In the circuit of Fig. 3, positions b and c of switch F2 are connected to one side of the power circuit from the plug B, while positions d and e are connected to one side of the secondary winding C2 of transformer C, the opposite side whereof connects to one end of a choke coil or inductance member G, the opposite side whereof connects to position e on F3. A like inductance H, is also connected between the sameside of the transformer secondary winding C2 and the position d on F3, while positions b and c on F3 are each in turn connected through inductances I and J direct to one side of the power circuit from the plug B opposite to that 'connecting positions b and c of F2. In passing, I wish to mention that a tapped choke may be most successfully used as an alternate and in lieu of the separate inductances G and J A neon glow lamp K is shunted across the contact arms E3 and E4, which has a resistance L placed across its terminals to reduce leakage which otherwise would be apparent, and

the test kit be plugged into llO volt, alternating l current at the socket B which connects to the primary windings CI of a transformer C. Tests conducted under paragraph 1I may use either direct or alternating current as the transformer is not employed, but under paragraph I, and by changing the characteristics of the transformer,

I am enabled to alter the current to meet thethe contact arms E and F are connected respectively, to two points of a four post socket M; a voltmeter N is shunted across these connections, one side of the line connecting in series a push button switch O and a two pole, single throw switch P with resistance PI, for changing over the voltmeter as will be hereinafter described. A second push button type switch Q is connected across the remaining two terminals of the socket M as shown.

The operation of the circuit shown at Figs. 3 and 4 will now be described as relating to the testing of a 11() volt 15 watt-lamp. The pointer on switch D is setto the position indicated on the panel as Lamp which places the contact arms on position b of both DI and D4. Power is next plugged into socket B, volts, 60 cycle. The pointer on switch F is then set to correspond to the wattage of the lamp under test, which in this case is 15 watt which places the contact arms on the position b of both'F2 and F3. 'I'he switch E is next adjusted until the lamp K and the inductance J are in series, which causes the lamp K to light, which indicates completion of the circuit. A set of four (2 pair) lamp test leads R are then plugged into the socket M, the opposite end of each pair terminating in a socket S which is adapted to engage the terminals of the lamp A in assembly. When this is done, the push button switch Q is closed momentarily, which closes the circuit across each end of the lamp, causing. the heating elements AI and A2 to glow and the lamp to light, thus manually duplicating the action of the usual starter switch. To check the line voltage, the lamp A is removed from the sockets S-S and the push button switch O is closed which cuts inthe voltmeter N directly across the line from the socket B.

When a 20 watt lamp is tested, the pointer on the switch F is moved' to the position indicated as 20 watt thus throwing in the inductance I which is of the propercharacteristics for'a 20 watt lamp; otherwise" the procedure is the same as for the 15 watt lamp.

For testing a 30 watt lamp, which usually requires 220 volts in place ofv 110 as heretofore, the pointer on F is adjusted to the position indicated as "30 watt 'which places the contact l arms on F2 and F3 in d position, so that the 5 power .instead of passing directly from the socket B as before, now is directed through the transformer C, which here is given a 2 to 1 ratio, so that the secondary C2 supplies the power at 220 volts -through the inductance H; otherwise the operation is the same as before described. And for a 40 watt lamp the inductance G is cut in, and the test carried out as heretofore. From the foregoing, it will be apparent that in testing I first provide a source of current to the plug B, which is adapted' to pass,veither as 110 or 220 volts, through the transformer C, through one portion of the variable impedance and inductive reactance G to J and through the lamp A in series, the rotary members of the gang switch F2 and F3 serving as a manually controlled means for mechanically synchronizing the selection of `both the impedance and the required voltage for the particular characteristics of the lamp under test, and that to obtain an indication of the lamp operation, I connect current responsive means, such as the voltmeter N and the glow lamp K across the electrodes AI and A2 of the lamp, and that further, the momentary closing of the switch Q cuts in that impedance 'G to J which has previously'been setup as a compensating reactan'ce across each cathode which momentarily serves as heating coils, and takes the place of the usual Vautomatic type starting\ switch.

In order to test control units such as reacters, including various forms of impedance, and to determine if too much or too little current will be allowed to flow through the lamp, and t0 40` check either external or internal shorts, IA deal with the eii'ect produced, and not the cause. Figs. 2 and 5 show the circuits I prefer to use for this purpose, Fig. 5 being only a portion`of Fig. 2 will be used as more clearly illustrating the principlesinvolved.

The number of control units now available and the variety of circuitsL in common use today are so large that .it is here impractical to discuss more than just a few in detail, and to describe volts.

the application of my test unit to these few only, it being manifest that many. others are equally applicable to the tests as are hereinafter described. And various manufacturers employ different methods of bringing out leads and color codes andfmarkings which may not be universally the same. In Fig. -5, I show the seven binding posts upon the panel which/are designated by the reference characters BI, B2, B3,

B4, Bs, Bs and B1, and to which the various leads i60,

from the control unit to be tested are connected.

The binding posts Bl and B2 are universally employed for connecting a starting compensator into the test circuit,"while B6 and B1 connect direct through T6 and T5, through the double 65 poledouble throw toggle switch T, either to l I3 volts through T3 and. T4; or in the alternate position, through TI and T2, thro ugh the secondary C2 of the transformer C, thus putting 220 volts across the line. /As a safety factor, the V connection offTl and T2, ,through the secondary of the transformer is controlled by the switch F2,rwhereon the positions d and e,- as before described are indicated on the dial as "30 watt mon to contact arm of switch E3; a voltmeter N is connected across the contact armsv of switches E3 and Ed, through the switch V, or through the switch O, and a single pole double throw switch the lamp A, having a cathode AI and anode A2, 15

like V, is likewise connected across E3 and E4.

and El and E2, the connection W2 whereof leads through a fixed resistance X to E2 and W4 through the binding post Bl and El. A socket Y of the type adapted to receive the plug-in type of cartridge starting switch is connected across the binding post B2 and the contact arm of the f switch E2 through a push button switch' YI. lThe binding postBl is connected on one side to the contact arm'of El, and on the other through a snap switch -Z to the bindingl post B2. The binding post B3 connects to ,position don DI; the post B4 to position d of D2; the post B5 to position d of D3; and the post B6 to position d of D4. The four contact arms of the selector switch D connect to the respective'positions on the selector switch E as follows: DI to c and e on El. and a, d and f of E3; D2 to d and f of El, c and e of E3, and a of E4; D3 to d and e of E2, b of E3, and c and f of E4; and D4 to c and f' of E2, and b, d and e of E4.

Particular reference to Fig. 5 is here made because Figs. 6 to 9 inclusive each include a simplfled drawing of the circuit shown at Fig. 5. I will now describe the operation of testing a -125 volt 15 or 20 watt reacter for use with external starting switch as shown at RI., Fig. 6 of the drawings. \is plugged into socketB and switch T set at 110 indicated on `the panel' to "correspond to the marked unit rating, which in this case will be either 15 watt or 20 watt which places the contact arm on F2 to either b or c position, which' under'test to the binding posts B3 and B1 as indicated at Fig. 6. Current responsive means such as the voltmeter N and the glow lamp K are con- Y nected across the reactor circuit by their respective switches as before described. In closing thev `circuit through theY selector switch E; the dial is rotated until upon contact the glow lamp lights. The lamp must light in one position only and not upon either position av or b, otherwise the unit undertest is not correct as to capacity 11 or otherwise defective. and 40 watt respectively, and the circuit cannot 75 A The control units under test are usually com- A source of power, 110 volts,

Selector switch F is set at the position ilar impedance R3 and condenser R4 in series.l

Each lamp circuit or reacter is tested individually. One lead from R2 connects to the binding post B1, and the other through the binding post B3, resistance U2 to the other side of the line, while the compensator leads connect to BI and B2, which also cuts the starting switch Y and the resistance X in series with the line, from where the test proceeds as before.

Fig. 8 illustrates another common type of control unit properly hooked up for test and wherein a single impedance R6 is provided with a built-in starting switch R1. As before, the' leads from the impedance R6 are connected respectively to the posts B3 and B1, but the leads from the starting switchR1 are connected to B4 and B5 unit comprising the usual impedance R8 connected in series with the secondary of a transformer R9, the leads whereof are connected to B3 and B6, and the primary to B1 as shown, so that the primary circuit is in series with the line through the posts B1 and B3, andthe secondary 2 circuit is in series with the line through the posts B6 and B3, so that independent tests of each may be conducted as before described.

' There are many other control units on the market today embodying various combinations of the general run as just shown and described, but their specific inclusion herein is not deemed necessary, as it is believed most evident that the examples given are indicative of the Aflexibility of my testing apparatus and amply illustrate its range of possibilities.

Starting switches of the external type, that is, those not already built into the control unit, are often times defective and require checking. These are usually of the plug-in or automatic type, and comprise a gas filled tube containing an anode and bi-metal cathode, which close the circuit upon heating and open upon cooling, although many of the other types including those employing heating coils are equally adaptable to test. For this purpose I employ the circuit ilin, so that the wiring can no longer be traced without destruction to the installation `and its attendant expense.v Therefore. my unit has been devised to meet the field requirements for a test .of the assembled and installed fixture, the circuit being particularly deiined at Figs. 12 and 13, as a part of Fig. 2, and in which case position c on the` switches DI, 2, 3 and I, which is indicated as Fixture" are connected to the four and starting 'switch are indicated as RIII and RI I respectively in the simplified schematic diagram of Fig, 13, lwhere the power for testing purposes is also indicated as supplied by the iix` ture per se.v And now as before, the switch F is moved to the indicated rating of the fixture, and the switch D to position c indicated as Fixture on the panel while the switch E is rotated to a position upon which the lamp K will glow. In this casein particular the switch E is truly a selector in that the operator, by its use, is enabled to pick. out a combination on E which will match any usual wiring of the fixture. For example.. if thelamp K lights on position a, it means that the line and the reactor are in series with the twoQterminals at one end only of the lamp fixturethis designates improper wiring; and should the lamp light on position b, the same condition prevails only at the opposite end or opposing 'lai'np fixture. In wiring the fixture, the

lustrated at Figs. 10 and 1l, and where, as before, the switch D is set at control unit, switch F at the known rating, and switch E to a point where the lamp K will glow. The starting switch to be tested is inserted in the socket Y so that the closing of switches W and Z will connect the resistance X in series with the inductive reactance J and the starting switch under test as shown at Fig. 11, and as before, the glow lamp K and volt meter N are connected across this circuit for obtaining an indication of the starter operal y leads may-become transposed, or in fitting the test plugfthey operator may or may not plug in to establishalcircuit as shown, and Ma may become Mb 4'01,"1Vld, or Md maybecome luc, or (Ma and Mb) and become (Md and Me). The switch E is specifically provided to meet a change in polarity orf-position. To illustrate, assume we substitute 'position-Ma with Mc; position Mb with Ma; and Mc with Md. Then the switch E is adjusteduntil the glow lamp lights, which in this case will `be on position c, which indicates an operable circuit.y And as before, the switch FI cuts in a portion' of the variable resistance U2 and the fixed inductance Ul which is connected in series with the reacter RII) und'er test, and the closing of the switch W places the resistance X in series with the starting switch RII, all as previously described, with the volt meter and glow lamp shunted across each circuit for obtaining an indication of their respective operations. Further, the fluorescent lamp to be used in the fixture Vunder test mayl also be tested individually, using the power taken from the fixture and following the details as before given.

For a lfield test kit only, I have provided a.

simplified test circuit as illustrated at Fig. 14, V

and wherein a .two gang, six position rotary type switch E5 and E6 performs the same functions as the switch EI, 2, 3 andJ of Fig. 12, and a double pole, double throw switch Fa corresponds to switch FI, a single pole double'throw switch Wa corresponds to switch W, a. single pole single cuit for the reacter RIZ through theA switch Fa` while a xed resistance IX is connected in series with the xture starting switch RIB as before, and current responsive means such as the volt meter `NI and glow lamp IK are likewise connected across both the reactor circuit and the starting switch circuit to obtain anindication of their respective operations. Binding posts Me, Mf, Mg and Mh are provided in lieu of the fixture test socket M1, to which the wires Mi, W, Mk and Ml leading from the socket M1 are adapted to connect, and the plug MB for the socket M1 carries two pair of two wire leads terminating in the plugs M4 and M6, adapted, respectively, to plug into the fixture sockets M3 and M5 for the purposes and of like effect as before described, and so that the reacter RIZ which is under test, may lbe connected in series with a portion of the variable resistance IU2 and the fixed inductance IUI, and the starting switch RI3 which is under test may be connected in series with the fixed my invention, what I arms adapted to be moved into engagement with currently contact separate terminals to close the circuit, a fixed inductance` and a variable resistance connected in parallel, a transformer,

manually operable means for connecting portions only of said variable resistance into the circuit mechanically f synchronized with `means for coupling alternate sides of said transformer into the circuit to concurrently correspond to the characteristics of the equipment under test, a xed resistance, means for cutting out of said circuit said fixed inductance and said' variable resistance and cutting in said fixed resistance in series in said circuit, a variable impedance and inductive reactance, manually operable means for connecting portions only of said variable impedance into the circuit mechanically syn'- chronized with said means for coupling alternate sides` of said transformer into the circuit, and current responsive means connected across said circuit for obtaining an indication of the operation ofithe equipment under test.

2. InL combinaion, a` testing circuit including current responsive equipment under test, a source of current-fonsaid circuit, means for controlling the connection of the equipment under test into said circuit, a fixed inductance and a variable resistance 'connected in parallel, a transformer, means for connecting portions only of said variable resistance into the circuit, means for couplingalternate sides of said transformer intothe circuit, a fixed resistance, means for cutting said iixed inductance and said variable resistance out of said circuit and cutting in said fixed resistance, a variable impedance and -inductive reactance, means for connecting portions only of said variable impedance into the circuit,

and current responsive means connected across said circuit for obtaining an indication of the operation of the equipment under test.

3. The combination with a testing circuit as per claim 1, which includes a current-actuated gstarting switch coupledand responsive to the Iiiow or current in said circuit. l

4. In an apparatus for testing current responsive equipment, a space discharge device 5 having cathode and anode electrodes associated therewith, a testing circuit including said device in series with a source of current, a variable impedance and inductive reactance, a. transformer, means for connecting portions only of said variable impedance. into said circuit in series with said device, means for introducing alternate sides of-said transformer into-the circuit, means for momentarily throwing the current across the respective cathode and anode 4of the device, and l5 current responsive means connected across said circuit for obtaining an indication of the operation of said device.

5. Testing apparatus as per claim 4, wherein the means for connecting portions only of said variable impedance into the circuit is synchronized with the means for coupling alternate sides of the transformer into the circuit to concur- 'rently correspond to the characteristics of the device.

including said impedance yin series with a source of current, a fixed inductance and a variable resistance connected in parallel, a transformer, means for connecting portions only of said variable resistance into the circuit, means for coupling alternate sides of said transformer into the circuit, and current responsive means connected across said circuit for obtaining an indication of the operation of said impedance.

7. Testing apparatus as per claim 6, wherein the means for connecting portions only of said variable resistance into the circuit is synchronized with the means for coupling alternate sides 'of the transformer into the circuit to concurrently correspond to the characteristics of the impedanceu 8. vTesting apparatusas per claim 6, which includes a current-actuated starting switch coupled and responsive to the flow of current in said circuit. A

'9. In an apparatus for testing current responsive equipment, a current-actuated starting 5 switch in series with a source of current, a fixed resistance, 'a variable impedance and capacitative reactance, a transformer, means for connecting portions only of said variable impedance into thel circuit, in series W`ithsaid fixed resistance, "0 means for coupling alternate sides of said transformer into the circuit, and current responsive means connected across said circuit for obtain- 11. In an\.apparatus`k for testing current responsive equipment, an impedance and'\ a currentactuated starting switch coupled and responsive tothe iiow of current through the impedance, a

testing circuit including said impedance and saidstarting switch in series with a source loi! current, a xed resistance, a fixed inductance and a variable resistance connected in parallel, means for 6. In an apparatus for testingcurrent responsive equipment, an impedance, a testing circuit switch, a testing circuit including said starting' connecting portions only of said variable resistance and said xed resistance into the circuit, vmanually operable means for controlling the connection of the combined impedance and starting switch into said circuit, said means comprising a selector switch having a number of contact terminals anda plurality of contact arms adapted to be moved into engagement with the respective terminals, each arm being mechanically -synchronized with the other to concurrently contact separate terminals to close the circuit, and current responsive means'connected across said circuit for obtaining an indication of the operation of said impedance and said starting switch.

GERALD WAYNE JAMES. 

